package com.thinkgem.jeesite.common.utils;

import java.math.BigDecimal;

public class ArithUtil
{
  private static final int DEF_DIV_SCALE = 10;
  
  public static double add(double d1, double d2)
  {
    BigDecimal b1 = new BigDecimal(Double.toString(d1));
    BigDecimal b2 = new BigDecimal(Double.toString(d2));
    return b1.add(b2).doubleValue();
  }
  
  public static double sub(double d1, double d2)
  {
    BigDecimal b1 = new BigDecimal(Double.toString(d1));
    BigDecimal b2 = new BigDecimal(Double.toString(d2));
    return b1.subtract(b2).doubleValue();
  }
  
  public static double mul(double d1, double d2)
  {
    BigDecimal b1 = new BigDecimal(Double.toString(d1));
    BigDecimal b2 = new BigDecimal(Double.toString(d2));
    return b1.multiply(b2).doubleValue();
  }
  
  public static double div(double d1, double d2)
  {
    return div(d1, d2, 10);
  }
  
  public static double div(double d1, double d2, int scale)
  {
    if (scale < 0) {
      throw new IllegalArgumentException("The scale must be a positive integer or zero");
    }
    BigDecimal b1 = new BigDecimal(Double.toString(d1));
    BigDecimal b2 = new BigDecimal(Double.toString(d2));
    return b1.divide(b2, scale, 4).doubleValue();
  }
}
